Possibly this is caused by pulling hairs and could be an attachment issue. Have you been wearing tight ponytails? You will want to discontinue doing so and see if this will resolve the pulling. It is best to wait a couple weeks before wearing high, tight ponytails. The extensions need to grow out a bit. If you're not wearing tight ponytails or other styles which might pull your hairs, remove any extensions which are causing these red bumps. Most times it's just an extension or 2 which may have been attached wrong and removing those particular bundles will eliminate the pulling and resulting red bumps.
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